I have long known that kale is supposed to be one of the healthiest vegetables around. I didn’t think I had tried it, but I was so wrong. The other day I looked up a translation to Swedish and for my Swedish friends in case you don’t know it is what we call grönkål. I haven’t had it often but as a southern Swedish tradition it is served as a side-dish to the Christmas ham. We have tried to find it here in Australia for Christmas but failed so we replaced it with spinach. Now I am going to renew my efforts to find kale because it is so highly spoken of.
Kale is a leafy green vegetable that belongs to the Brassica family, a group of vegetables including cabbage, cauliflower, and Brussels sprouts. Curly kale has ruffled leaves and a fibrous stalk and is usually deep green in color. It has a lively pungent flavour with delicious bitter peppery qualities. It carries more nutritional value for fewer calories than almost any other food around. Although it can be found in markets throughout the year, it is in season from the middle of winter through the beginning of spring when it has a sweeter taste and is more widely available. If you are to believe the literature it has remarkable properties.
The good side
In a previous blog we covered cholesterol and the minimal impact cholesterol-containing foods have on cholesterol blood levels. But there is more. Without going into too much detail, our own cholesterol is metabolised in the liver to bile acids, which are released into the intestine. But here most of it is reabsorbed in an essential process for the digestion and absorption of dietary fats. Now kale has been found to contain a group of resins known as bile acid sequestrants, which have been shown to lower cholesterol and decrease absorption of dietary fat. The cholesterol-lowering components do a better job of binding together with bile acids in the digestive tract when kale has been steamed. Although cholesterol is essential to the body, too much is no good as we all know.
And there are anti-cancer compounds. Kale, as with broccoli and other brassicas, contains sulforaphane (particularly when chopped or minced), a chemical with potent anti-cancer properties. Sulforaphane is an antioxidant and stimulator of natural detoxifying enzymes and, together with indole-3-carbinol, a chemical also found in kale which boosts DNA repair in cells, may reduce the risk of breast, bladder and prostate cancer. Epidemiological studies show that people who eat a lot of cruciferous vegetables have reduced incidences of cancer. In-vitro and animal studies have confirmed the anti-cancer effects and have demonstrated a reduction in frequency, size, and number of tumours. However, since boiling destroys much of the sulforaphane, steaming, microwaving, or stir frying is preferred to retain the activity of the compound.
Kale is very high in beta carotene, vitamin K, vitamin C, and rich in calcium. It is also a source of two carotenoids, lutein and zeaxanthin and a large number of flavonoids. Many of the flavonoids in kale are also now known to function not only as antioxidants, but also as anti-inflammatory compounds. It might sound too good to be true so I better stop there before I go overboard.
The bad side
There is another side of kale you should know about before rushing head on. It is among a small number of vegetables, including rhubarbs that is the most well-known, that contain measurable amounts of oxalates. When oxalates become too concentrated in body fluids, they can crystallize and cause health problems. For this reason, individuals with already existing and untreated kidney or gallbladder problems may want to avoid eating kale.
It might also pay off to buy organic kale since conventionally grown kale has been found to carry fairly high pesticide levels in some countries. However, finding organically grown kale should not be that difficult since it is a popular crop with organic farmers.
Enjoy your kale and live a long and healthy life.
- Much Ado About Kale (lettuceeatgreen.org)
- The Benefits of Eating Green (Vegetables, That is!) (natural-holistic-health.com)
- Kale (thewistfulspirit.wordpress.com)
- Gemelli Pasta with Kale Pistou (delicious2013.wordpress.com)
- 10 Ways to Eat Kale Like a Superstar (onegreenplanet.org)
- Crispy Kale Chips in 12 Minutes (beyondboulevard.wordpress.com)
- Kale Salad (timefortidbits.com)